Question

the electron dot diagram shows the arrangement of dots without identifying the element.
which elements symbol could replace the question mark in the diagram?
○ boron (b)
○ neon (ne)
○ rubidium (rb)
○ arsenic (as)

Explanation:

Step1: Count valence electrons

The electron dot diagram has 5 dots, so the element has 5 valence electrons.

Step2: Check each option's valence electrons

• Boron (B): Group 13, 3 valence electrons
• Neon (Ne): Group 18, 8 valence electrons
• Rubidium (Rb): Group 1, 1 valence electron
• Arsenic (As): Group 15, 5 valence electrons

Answer:

D. arsenic (As)